Bandalero Ranch Blog

In light of the recent cases reported in southern Arizona, the following is a basic overview of the viral disease Vesicular Stomatitis. In the United States this virus generally occurs in the Southwestern and Western states with a wide variation in number of cases that occur and locations that are affected each year. It can also occur in Central and South America. In 2014 there were cases reported in the states of TX, CO, and NE. In Arizona the last outbreak was reported in 2010.

Appearance of the virus often occurs during warmer months and its spread is not fully understood. Factors that have been identified in the spread of the virus include: insect vectors (e.g. flies), mechanical transmission, and movement of exposed/affected animals. Spread between animals occurs with contact or exposure to saliva of infected animals and/or fluid from ruptured vesicles.

Animal affected include horses, cattle, as well as occasionally swine, sheep, goats, llamas, and alpacas. Horses tend to be the most sensitive and severely affected, but there can be great economic loss for dairy cattle due to lesions of the teat and secondary infection of the udder (i.e. mastitis). The incubation period ranges from 2 to 8 days. The disease is characterized by blister-like lesions that can occur in the mouth (i.e. tongue, gums, lips, dental pad, etc), coronary band/foot, vulva, prepuce, and teats/udder. Fever can also occur immediately proceeding or at the time of lesions first appearance.

In the horse specifically lesions usually occur on the tongue, lips, around the nostrils, corners of the mouth, gums, as well as coronet band and ventral abdomen. Most animals recover in approximately 2 weeks unless secondary infection occurs.

In rare cases humans can be infected with the disease. Symptoms of illness include fever, muscle aches, headache, and malaise similar to influenza. Most cases of infection are associated with the handling of infected animals and protective clothing, gloves, and hygiene should be used to protect oneself.

There is no cure or vaccination for Vesicular Stomatitis only supportive care for affected animals. In cases of confirmed outbreaks measures are taken to contain the infection and stop the spread. These include:

Separation of animals with lesions from healthy animals

Halting of any movement of animals from affected premises at least 21 days AFTER lesions in the last affected animals have healed.

On-farm insect control programs such as eliminate/reduce insect breeding areas and use of insecticide sprays (for premises and animals)

Protective gear for personnel handling affected animals

Confirmation of Vesicular Stomatitis is diagnosed via viral isolation from samples of lesions, blister fluid, or antibody testing of serum from affected animals. If there is concern that an animal is affected with Vesicular Stomatitis, regardless of species, contact your veterinarian so that the proper examination and diagnostic tests can be performed and other animals in the vicinity can be protected. For more information please see the following links:

Now that long awaited foals are on the ground and learning to run, buck, and play, it is time to consider measures that you as an owner can take to help them have a long happy life. One of these preventative health measures is vaccination against diseases that can have devastating effects on the horse including Tetanus, Eastern and Western Equine Encephalitis Viruses (aka Sleeping Sickness), Equine Herpes Virus (aka Rhinopneumonitis), Equine Influenza, West Nile Virus, and Rabies.

These diseases are all potential pathogens that your young foal may encounter at some point in their life. Although in your own personal horse community diseases like Sleeping Sickness may not seem like much of a threat, yet there are still cases that occur annually in which the horses that are infected become gravely ill, and may have lasting effects from the disease if they are lucky enough to survive, not to mention the monetary costs of supportive care to be treated while ill.

The protective antibodies produced as a result of vaccination are not only helpful in preventing disease, but they can also be the difference in living or dying after expose to a particular pathogen. A good example of this is West Nile Virus, which was considered to be very deadly for horses in the years following its arrive to the United States back in the 1999. The mortality rate (e.g. risk of dying from having disease) is considered to be about 33% for horses that contract West Nile Virus infections, but what is more important is that over 90% of non-vaccinated horses when infected developed grave clinical signs such as inability to stand and/or complete loss of ability to eat/drink that resulted in their death or humane euthanasia. By simply vaccinating your foals you give them a fighting chance against a disease that has proven in recent years it is still very much a problem. From personal experience of cases I saw in Louisiana in 2012, the two horses that survived out of the three we treated for confirmed West Nile infections had been vaccinated, while the third had not. Despite full supportive care, this unvaccinated filly quickly became severely uncoordinated, lost the ability to stand and then began having seizure like episodes before the owner elected to euthanize and stop her suffering. In these aggressive diseases, preventative care such as vaccination is often our best treatment.

That being said the American Association of Equine Practitioners in an effort to promote the health of the horse has put together a list of core vaccines that all horses should have regardless of where they reside in North America. This includes Tetanus, Eastern/Western Encephalitis, West Nile, and Rabies. Additionally vaccination for Equine Herpes Virus (e.g. EHV- 1 and 4) and Equine Influenza is also recommended for horses that will be showing, racing, or are house in densely horse populated areas such as boarding and breeding facilities. Because these are common pathogens that are easily spread between horses it is also a good idea to give foals an early advantage by vaccinating them against these diseases.

To help get the most protection out of vaccinating your foal it is best to vaccinate at specific times in the first year of the foals life. Below is a table that outlines the current recommendations for foal vaccinations:

Since there are difference types of vaccination products for diseases like West Nile and Equine Influenza consulting with your veterinarian will be the most effective way to create a vaccination program that will best benefit your foal. Also every situation is different and your veterinarian can help determine other pathogens your foal may at higher risk for based on geographical location and how the horses on your property intermingle. Examples of some other diseases to ask you veterinarian about vaccination for would be Strangles and Botulism as these can be huge problems for foals in certain circumstances.

Every day we submit blood samples to our laboratories for horses that are obtaining health certificates in order to attend shows or sales. What is a Coggins test. Why do we do it?

The test is looking for the reaction of the body to the virus that causes Equine Infectious Anemia,

The Coggins test is the named after the veterinarian, Dr Leroy Coggins, that created the special test that identifies the immune response, or antibodies to the Equine Infectious Anemia Virus (EIAV).

EIA affects all species of equine, horses, donkeys, mules, zebras and ponies. The disease is distributed around the world. It was first described and identified in France in 1843. In the US only about 20% of all horses are routinely tested. Our prevalence is basically unknown.

Our most recent national outbreak occurred in Arkansas last year affecting 40 horses from one facility. The incidence is highest in those states with a larger population of horse flies and deerflies.

Infection with the EIA Virus results in recurrent episodes of cyclic fevers, lethargy, ventral edema, unexplained weight loss, anemia, bruises on the gums and other mucosa, and occasionally death. Most horses have an immune response which will gradually control the disease within a year, and then will no longer show any sign of the disease. Unfortunately these horses will be carriers of the virus for life.

Notice machete like mouth parts

They may appear normal, but serve as a reservoir of infection for uninfected horses through the bites of flies, or other biological vectors.

Diagnosis is based primarily on serological testing. There is no treatment. The US prohibits interstate travel of infected animals, and has attempted to prevent the spread of the disease by requiring every horse that crosses any state line to be negative. States are variable in their requirements. Some states ask that the horse have a negative test within 12 months, others within 6 months.

There are essentially three stage of the disease process. The acute phase begins approximately 4 weeks post exposure. The chronic phase lasts approximately one year, and the carrier or persistent phase endures for the rest of the horses lifespan.

The symptoms are variable and depend on the stage of the disease. Acutely, the horse has a high fever, lethargy, ventral edema, and bleeding from the nose. The acute stage is usually less than a week, and frequently goes completely unnoticed.

The chronic part of the disease results in repeated bouts of the above symptoms, gradually reducing in severity. Weight loss may be observed as the horse struggles to maintain normal blood values. After one year, the horse will usually no longer have any symptoms at all. Most horses appear completely normal.

EIA is caused by a virus that is very closely related to HIV. The body may learn to adjust to it, but it never can completely clear it. The virus cannot affect people or any other animals other than members of the equine family. Any sort blood to blood transmission can pass the virus.

Horse Fly

Biting flies, sexual intercourse, or reused needles and surgical instruments can all pass the virus.

There is no specific treatment other than supportive for EIA. Because EIA is a reportable disease in the United States, positive horses may only be isolated from all other horses, euthanized, or transported to a recognized research facility. If the horse is not euthanized, they are branded on the jaw with a specific two digit state code followed by the letter A, then a second two digit number specifying that specific horse .

The virus is not long lived outside of the horses body, and the contamination area is considered to be 200 yards (assuming this is accounting for the distance of the flys flight path)

Preventive vaccines are not yet available, and it is because of our governmental strict surveillance that this disease has been controlled in our country. Outbreaks can and do still occur. Testing should occur as a normal yearly check up, and before admitting any new horse to any facility. Horses should never be injected with previously used needles, and fly control should be rigorously applied.

On August 31, 2012 I posted a image of the vasculature of the hoof on our facebook page; consquently, I have received a great deal of interest. This is an excellent way to introduce the condition of laminitis which is commonly called founder.

The introduction to laminitis as written by Dr. Stashak himself describes inflammation of the lamina as a gross oversimplification of a

Vasculature of Hoof

complicated, interrelated sequence of events that result in varying degrees of breakdown of the interdigitation of the primary and secondary epidermal and dermal lamellae in the foot. If you understood that and want a further more detailed description, then this article is not for you. This is laminitis made understandable.

As you may have now surmised, the blood flow to the foot is very delicate. When a horse has circulating digestive toxins from eating a large amount of grain, eating extremely lush pasture, eating an overly rich cutting of alfalfa, or possibly being switched from a low energy diet to a high energy diet, the horse can create swelling in and around those fragile vessels. This is similar to the feeling of water retention or bloat that we feel whenever we eat at an all-you-can-eat Chinese buffet, or spend too much time grazing at a wedding reception or an office party. The next morning you have a difficult time getting your rings on or off your fingers. Your shoes may feel too tight.

Chronic founder, years of poor blood flow have allowed the bone of the foot to atrophy.

Another common cause of laminitis is illness. Peritonitis, retained placenta, pregnancy, bacterial or viral infections can all cause founderalso. Circulation can be compromised during illness and may pool in the extremities as the body is out of balance. This is further complicated in the horse, because all of the extremities are as low as you can get. Gravity does not help to reduce the pooling effect. A horse can also have traumatic laminitis. This may be referred to as road founder. It occurs after a horse had been ridden long, fast, or carried a heavy load on hard or rocky ground. Human marathon runners probably have a similar feeling, but even just standing on the cement in our laboratory for a prolonged period of time can make my feet ache.

Finally, there is yet another way that we can create founder. A horse was not designed to bear weight on only one opposing limb. There are no three legged horses. When a horse cannot stand on one hoof, the other hoof must do the work of two for prolonged periods of time. The horse has a special tissue on the bottom of the foot that is part of the sole. It is called the frog. It is soft and pliable compared to the rest of the hard sole. When the horse puts pressure on the frog, the frog pushes up against the vasculature on the coffin

Acute founder, a gas line can actually be seen between the bone and the hoof wall.

bone and catapults it out of the foot. A standing horse that cannot walk, cannot utilize this mechanism. This further increases the combination of increased weight load, inflammatory products in the body from an opposing limb fracture, and just plain gravity. To the sorrow of millions, this is why Barbaro was put to sleep. His fractured leg could not bear weight so the opposite rear foot finally foundered.

The problem with the horse is that the hoof wall acts as a complete cast around the entire foot. As you can see from the blood supply, a very protective suit of armor was necessary. But really good armor does not expand. If the tissue inside the hard hoof begins to swell, it has nowhere to go. This can cause microtrauma to the tiny linkages (lamellae) that hold the hoof wall to the bone and its blood supply. These tiny connections hold the bone within the foot and literally the weight of the horse suspended above the sole of the hoof. The tiny bonds break and the coffin bone actually rotates and sinks, just like the Titanic.

If you have ever lost a finger or toe nail you have experienced the same thing. This is life threatening to the horse. The horse cannot stand on the bone of his foot while he grows a new nail.

Healing after an injury or strain involves an orchestrated series of events. The proteins in the blood promote effective repair. The highest concentration of these proteins is held within the special blood cell fragments for clotting called platelets. Platelets are formed in the bone marrow and flow within the blood stream in a quiet state. When an injury occurs, the platelets are activated are gather at the injury site just like an angry mob. They release beneficial proteins called growth factors. (This is better than an angry mob throwing rocks or bad fruit). This is the first step to the healing process.

Just as the computer industry grows exponentially, so does the medical field. Often the Veterinary field is actually ahead of human practice since most of the products are used on animals first. There are many different regenerative medical options available and many of them we can actually mix and match. I wanted to start today with the fastest and most financially affordable of the three most popular treatments. Autologous Conditioned Plasma (ACP) or Platelet Rich Plasma (PRP)-Dont stop reading!!!!, Im going to get simple now; they are derived from your animals own personal blood. We take a simple collection of a mere 10 ccs of blood, using a special double syringe. We spin it in a centrifuge which has a rotor arm specifically designed for this purpose. This occurs immediately after the blood draw, and the ACP is available for stall side treatment in less than an hour.

The plasma containing the concentrated healing factor is then injected into the injured ligament, tendon, joint, or wound. Often we assist the deposition of the ACP using ultrasound guidance.

Unlike the corticosteroids that we have always used in the past, there is no harmful effect. The cartilage is not degraded and the immune system is not depressed. ACP uses the patients own natural healing properties to treat the injury.

Tears, defects, degeneration or inflammation can often be treated successfully with ACP. It can also be a beneficial additional treatment to a site that has had a recent catastrophic injury. Picture a horse that has recently sat on a metal t-post. The sutures can pull the torn muscle together, but they would definitely appreciate some assistance. Then those large muscles that are basically tenuously basted together can mend with a more perfect matrix, rather than a cross hatched scar knitting them together.

ACP has shown significant promise for improving pain relief and function in the treatment of arthritis. The possibility of providing a treatment using the patients own blood products to soothe this common crippling disease is a huge benefit for veterinarians and their patients.

It is monsoon season and for Tucsonans that can only mean closed roads and mosquitoes. Mosquitoes are the known vector for West Nile Disease. This year, we are seeing a particularly high rise in the West Nile disease rate. According to the CDC it is at its highest level since its first detection in 1999. The most publicized outbreak is occurring in the Dallas/ Fort Worth area, but I have now had two positive cases in my practice area. The first was an unvaccinated horse, which is really taking a great risk. The other was in a yearling. The yearling had received his two sequential weanling shots, and then had been boostered in his yearling year prior to the monsoon season. He was confirmed as positive just last week. Because he was young, his immune system may not have had enough stimulation as a weanling. His protective titer may have been low. This is a very good example of why we recommend fall and spring vaccination, and for heavily exhibited animals, we additionally recommend they receive flu and rhino vaccines quarterly. The AAEP recommends once a year, but in areas with short mild winters and long summers, like Texas and Arizona, most veterinarians recommend twice yearly.

The West Nile Virus is not passed from horse to horse or from human to horse. The only way that the horse can get the virus is from the bite of a mosquito. Most horses that contract West Nile are asymptomatic, or may have very transient fever. Unfortunately there is a small percentage that will develop neurological symptoms. Some signs are as simple as drowsiness or in coordination; other far worse signs are actual decumbency, unable to rise. If you suspect your horse may be infected, a simple blood test can be run right here at our own University of Arizona Veterinary Diagnostic Laboratory. Then you can determine a course of treatment before the disease progresses too far. Antitoxin is available and supportive care is mandatory. The mortality rate for West Nile horses that have neurological disease is pretty bad. Many horses survive but have lasting neurological impairment.

Vaccinated horses that do become sick with the West Nile Virus are usually less sick, require less intensive treatment, and get better faster, with a better outcome. Also, please try to keep your horse protected from mosquitoes by reducing the amount of standing water and spray, spray, spray.

If you have not had your horses vaccinated yet, it is not too late. Please get a West Nile booster. If your horse has never had a West Nile Vaccine, he will need two sequential shots 4-8 weeks apart. It is a good idea to have the veterinarian do a physical exam, even a brief one. Your horse may need dental work, or may have developed a heart murmur. Remember that many problems go unnoticed until they are serious and expensive to treat. Call today for your West Nile Vaccination 520-760-6200.

For more information on Clinical Signs of a a horse infected with West Nile.

By Patrick M. McCue, DVM, PhD,
Diplomate American College of Theriogenologists
The placenta is the connection between the developing fetus and the mare and provides the means for obtaining nutrition and for gas exchange. Examination of the placenta can offer valuable insight into the health of the newborn foal. Consequently, it is recommended that owners, farm managers or foaling attendants perform an evaluation of each placenta.

The placenta is normally passed within three hours after foaling. Once passed, the placenta should be immediately removed from the foaling area and rinsed free of gross debris. Disposable plastic or latex gloves should be worn during handling and examination. If possible, the weight of the placenta should be determined. An inexpensive bathroom scale is sufficient. Under normal circumstances, the weight of the placenta will be approximately 11 % of the body weight of the foal.
An increased weight may be the result of edema associated with factors such as fescue toxicosis or may be due to aninfectious condition such as placentitis. Both conditions may be associated with a medically compromised fetus.

The placenta consists of three primary components, the outer placental membrane or chorioallantois, the inner placental membrane or amnion, and the umbilical cord. In a normal foaling, the thicker outer placental membrane is almost always turned inside-out as the placenta is passed.

For examination, the outer placental membrane should be turned right-side out and then spread out on a clean flat surface. The allantoic (side toward the foal) surface is smooth and pink and blood vessels are visible coursing along its surface. The chorionic (side toward the uterus) surface has a brick-red velvety appearance due to the presence of structures known as
microcotyledons. Microcotyledons are the microscopic villi or finger-like projections that provide the Velcro-like attachment of the placenta to the uterine lining.

The membranes may be laid out with the chorioallantois in an F or Y shape, with the two horns of the placenta forming the arms of the F or Y and the body of the placenta forming the base. The umbilical cord and amnion should protrude from the base or body of the placenta.

One of the first things that may be noted is that the tips of the placental horns differ significantly in size and thickness. The larger horn housed the fetus and is referred to as the pregnant horn. The tip of the pregnant horn is always thicker than the tip of the smaller (non-pregnant horn).

The placenta should be examined to determine if it was passed intact or if a piece is missing and potentially still inside the mare. By far the most likely portion of the placenta that may be retained is the thin tip of the nonpregnant horn. Retention of even a small piece of placenta in the uterus poses a very serious threat to the health of the mare.

The area of the body of the placenta that was in direct contact with the cervix of the mare will be pale in color and devoid of the red velvety microcotyledons. This area is referred to as the cervical star region of the chorionic surface of the placenta. Ascending bacterial infections that pass through the cervix may result in thickening or the presence of a mucus-like exudate
in the area around the cervical star. If a placental infection is present, the foal may have been exposed to pathogenic micro-organisms prior to being born and should be considered high-risk for medical complications.

The thin, white amnion should be examined next. The primary abnormality that may be noted in the amnion is a yellow-orange discoloration due to meconium staining. Stress to the fetus prior to birth may result in premature passage of fecal material (meconium). Meconium staining may be an early warning sign that the foal is compromised. In addition, affected foals may aspirate meconium into their lungs and develop serious respiratory complications.

The umbilical cord will virtually always have a mild to moderate degree of twisting present. Excessive twisting of the cord can result in decreased blood flow from the placenta to the fetus and other problems.

Evaluation of the placenta is a valuable procedure that can positively impact the health and welfare of both the newborn foal and the mare. It is recommended that your veterinarian be contacted for an initial lesson in field evaluation of the placenta and that he or she be notified if abnormalities are identified in subsequent placental examinations.